Page 78 - Moving the Earth_ The Workbook of Excavation
P. 78

SURVEYS AND MEASUREMENTS

                   2.28   THE WORK





































                               FIGURE 2.24  Gradient readout. (Courtesy Laser Alignment Inc.)



























                                      FIGURE 2.25  Lining up the beam. (Courtesy of AGL Lasers.)
   73   74   75   76   77   78   79   80   81   82   83